This invention is generally directed to benzopyranone compounds, compositions comprising the benzopyranone compounds and methods for treating a bone-resorbing disease, cancer, arthritis or an estrogen-related condition, comprising administering an effective amount of a benzopyranone compound to a patient in need thereof.
The estrogen hormone has a broad spectrum of effects on tissues in both females and males. Many of these biological effects are positive, including maintenance of bone density, cardiovascular protection, central nervous system (CNS) function, and the protection of organ systems from the effects of aging. However, in addition to its positive effects, estrogen also is a potent growth factor in the breast and endometrium that increases the risk of cancer.
Until recently, it was assumed that estrogen binds to a single estrogen receptor (ER) in cells. As discussed below, this simple view changed significantly when a second ER (ER-xcex2) was cloned (with the original ER being renamed ER-xcex1), and when co-factors that modulate the ER response were discovered. Ligands can bind to two different ERs which, in the presence of tissue-specific co-activators and/or co-repressors, bind to an estrogen response element in the regulatory region of genes or to other transcription factors. Given the complexity of ER signaling, along with the tissue-specific expression of ER-xcex1 and ER-xcex2 and its co-factors, it is now recognized that ER ligands can act as estrogen agonists and antagonists that mimic the positive effects, or block the negative effects, of estrogen in a tissue-specific manner. This has given rise to the discovery of an entirely new class of drugs, referred to as Selective Estrogen Receptor Modulators or SERMs. These drugs have significant potential for the prevention and/or treatment of cancer and osteoporosis, as well as cardiovascular diseases and neurodegenerative diseases such as Alzheimer""s disease.
Bone-resorbing diseases, such as osteoporosis, are debilitating conditions which affect a wide population, and to which there is only limited treatment. For example, osteoporosis affects about 50% of women, and about 10% of men, over the age of 50 in the United States. In individuals with osteoporosis, increased loss of bone mass results in fragile bones and, as a result, increased risk of bone fractures. Other bone-resorption diseases, such as Paget""s disease and metastatic bone cancer, present similar symptoms.
Bone is a living tissue which contains several different types of cells. In healthy individuals, the amount of bone made by the osteoblastic cells is balanced by the amount of bone removed or resorbed by the osteoclastic cells. In individuals suffering from a bone-resorbing disease, there is an imbalance in the function of these two types of cells. Perhaps the most well known example of such an imbalance is the rapid increase in bone resorption experienced by postmenopausal women. Such accelerated bone lose is attributed to estrogen deficiency associated with menopause. However, the mechanism of how the loss of estrogen results in increased bone resorption has long been debated.
Recently, investigators have suggested that an increase in bone-resorbing cytokines, such as interleukin-1 (IL-1) and tumor necrosis factor (TNF), may be responsible for postmenopausal bone loss (Kimble et al., J. Biol. Chem. 271:28890-28897, 1996), and that inhibitors of these cytokines can partially diminish bone loss following ovariectomy in rodents (Pacifici, J. Bone Miner Res. 11: 1043-1051, 1996). Further, discontinuation of estrogen has been reported to lead to an increase in IL-6 secretion by murine bone marrow and bone cells (Girasole et al., J. Clin. Invest. 89:883-891, 1992; Jilka et al., Science 257:88-91, 1992; Kimble et al., Endocrinology 136:3054-3061, 1995; Passseri et al., Endocrinology 133:822-828, 1993), antibodies against IL-6 can inhibit the increase in osteoclast precursors occurring in estrogen-depleted mice (Girasole et al, supra), and bone loss following ovariectomy does not occur in transgenic mice lacking IL-6 (Poli et al., EMBO J. 13:1189-1196, 1994).
Existing treatments for slowing bone loss generally involves administration of compounds such as estrogen, bisphosphonates, calcitonin, and raloxifene. These compounds, however, are generally used for long-term treatments, and have undesirable side effects. Further, such treatments are typically directed to the activity of mature osteoclasts, rather than reducing their formation. For example, estrogen induces the apoptosis of osteoclasts, while calcitonin causes the osteoclasts to shrink and detach from the surface of the bone (Hughes et al., Nat. Med. 2:1132-1136, 1996; Jilka et al., Exp. Hematol. 23:500-506, 1995). Similarly, bisphosphonates decrease osteoclast activity, change their morphology, and increase the apoptosis of osteoclasts (Parfitt et al., J. Bone Miner Res. 11: 150-159, 1996; Suzuki et al., Endocrinology 137:4685-4690, 1996).
Cytokines are also believed to play an important role in a variety of cancers. For example, in the context of prostate cancer, researchers have shown IL-6 to be an autocrine/paracrine growth factor (Seigall et al., Cancer Res. 50:7786, 1999), to enhance survival of tumors (Okamoto et al., Cancer Res. 57:141-146, 1997), and that neutralizing IL-6 antibodies reduce cell proliferation (Okamoto et al., Endocrinology 138:5071-5073, 1997; Borsellino et al., Proc. Annu. Meet. Am. Assoc. Cancer Res. 37:A2801, 1996). Similar results have been reported for IL-6 with regard to multiple myeloma (Martinez-Maza et al., Res. Immunol. 143:764-769, 1992; Kawano et al., Blood 73:517-526, 1989; Zhang et al., Blood 74:11-13, 1989; Garrett et al., Bone 20:515-520, 1997; and Klein et al., Blood 78:1198-12-4, 1991), renal cell carcinoma (Koo et al., Cancer Immunol. 35:97-105, 1992; Tsukamoto et al., J. Urol. 148:1778-1782, 1992; and Weissglas et al., Endocrinology 138:1879-1885, 1997), and cervical carcinoma (Estuce et al., Gynecol. Oncol. 50:15-19, 1993; Tartour et al., Cancer Res. 54:6243-6248, 1994; and Iglesias et al., Am. J. Pathology 146:944-952, 1995).
Furthermore, IL-6 is also believed to be involved in arthritis, particularly in adjuvant-, collagen- and antigen-induced arthritis (Alonzi et al., J. Exp. Med. 187:146-148, 1998; Ohshima et al., Proc. Natl. Acad. Sci. USA 95:8222-8226, 1998; and Leisten et al., Clin. Immunol. Immunopathol 56:108-115, 1990), and anti-IL-6 antibodies have been reported for treatment of arthritis (Wendling et al., J. Rheumatol. 20:259-262, 1993). In addition, estrogen has been shown to induce suppression of experimental autoimmune encephalomyelitis and collagen-induced arthritis in mice (Jansson et al., Neuroimmunol. 53:203-207, 1994)
The cytokine IL-6 has also been shown to be an important factor in inducing the formation of osteoclasts (Girasole et al., supra; Jilka et al. (1992), supra; Jilka et al. (1995), supra; Kimble et al. (1995), supra; Pacifici et al., supra; and Passeri et al., supra). Other investigators have shown that administration of the neutralizing antibody, antisense oligos, or the Sant 5 antagonist against IL-6, reduces the number of osteoclasts in trabecular bone of ovariectomized mice (Devlin et al., J. Bone Miner 13:393-399, 1998; Girasole et al., supra; Jilka et al. (1992), supra, and Schiller et al., Endocrinology 138:4567-4571, 1997), the ability of human giant cells to resorb dentine (Ohsaki et al., Endocrinology 131:2229-2234, 1993; and Reddy et al., J. Bone Min. Res. 9:753-757, 1994), and the formation of osteoclasts in normal human bone marrow culture. It has also been found that estrogen downregulates the IL-6 promoter activity by interactions between the estrogen receptor and the transcription factors NF-xcexaB and C/EBPxcex2 (Stein et al., Mol. Cell Biol. 15:4971-4979, 1995).
Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been suggested to play a role in the proliferation of osteoclastic precursor cells. In long term cultures of human or mouse bone marrow cells or peripheral blood cells, GM-CSF promotes the formation of osteoclastic cells (Kurihara et al., Blood 74:1295-1302, 1989; Lorenzo et al., J. Clin. Invest. 80:160-164, 1987; MacDonald et al., J. Bone Miner 1:227-233, 1986; and Shinar et al, Endocrinology 126:1728-1735, 1990). Bone marrow cells isolated from postmenopausal women, or women who discontinued estrogen therapy, expressed higher levels of GM-CSF than cells from premenopausal women (Bismar et al., J. Clin. Endocrinol. Metab. 80:3351-3355, 1995). Expression of GM-CSF has also been shown to be associated with the tissue distribution of bone-resorbing osteoclasts in patients with erosion of orthopedic implants (Al-Saffar et al., Anatomic Pathology 105:628-693, 1996).
As noted above, it had previously been assumed that estrogen binds to a single estrogen receptor (ER) in cells, causing conformational changes that result in release from heat shock proteins and binding of the receptor as a dimer to the so-called estrogen response element in the promoter region of a variety of genes. Further, pharmacologists have generally believed that non-steroidal small molecule ligands compete for binding of estrogen to ER, acting as either antagonists or agonists in each tissue where the estrogen receptor is expressed. Thus, such ligands have traditionally been classified as either pure antagonists or agonists. This is no longer believed to be correct.
Rather, it is now known that estrogen modulates cellular pharmacology through gene expression, and that the estrogen effect is mediated by estrogen receptors. As noted above, there are currently two estrogen receptors, ER-xcex1 and ER-xcex2. The effect of estrogen receptor on gene regulation can be mediated by a direct binding of ER to the estrogen response element (ERE)xe2x80x94xe2x80x9cclassical pathwayxe2x80x9d (Jeltsch et al., Nucleic Acids Res. 15:1401-1414, 1987; Bodine et al., Endocrinology 139:2048-2057, 1998), binding of ER to other transcription factors such as NF-xcexaB, C/EBP-xcex2 or AP-1xe2x80x94xe2x80x9cnon-classical pathwayxe2x80x9d (Stein et al., Mol. Cell Biol. 15:4971-4979, 1995; Paech et al., Science 277:1508-1510, 1997; Duan et al., Endocrinology 139:1981-1990, 1998), and through non-genomic effects via extranuclear estrogen receptor signaling that potentially include plasma membrane ER (Nadal, A. et al., Trends in Pharmacological Sciences 22:597-599, 2001; Wyckoff, M. H. et al., J. Biol. Chem. 276: 27071-27076, 2001; Chung, Y-L. et al., Int. J. of Cancer 97:306-312, 2002; Kelly, M. J. et al., Trends Endocrinol. Metab. 10:369-374, 1999; Levin, E. R. et al., Trends Endocrinol. Metab. 10:374-377, 1999).
Progress over the last few years has shown that ER associates with co-activators (e.g., SRC-I, CBP and SRA) and co-repressors (e.g., SMRT and N-CoR), which also modulate the transcriptional activity of ER in a tissue-specific and ligand-specific manner. In such cases, ER interacts with the transcription factors critical for regulation of these genes. Transcription factors known to be modulated in their activity by ER include, for example, AP-1, NF-xcexaB, C/EBP and Sp-1. In addition, orphan nuclear receptors, such as estrogen receptor-related receptors xcex1, xcex2, xcex3 (ERR-xcex1, ERR-xcex2, ERR-xcex3), have been identified. Although estradiol does not appear to be a ligand for the ERRs, some SERMs and other traditional ER-ligands have been shown to bind to the receptors with high affinity (Coward, P. et al., Proc. Natl Acad. Sci. 98:8880-8884, 2001; Lu, D. et al., Cancer Res. 61:6755-6761, 2001; Tremablay, G. B. et al., Endocrinology 142:4572-4575, 2001; Chen, S. et al., J. Biol. Chem. 276:28465-28470, 2001).
Furthermore, ER-xcex1 and ER-xcex2 have both overlapping and different tissue distributions, as analyzed predominantly by RT-PCR or in-situ hybridization due to a lack of good ER-xcex2 antibodies. Some of these results, however, are controversial, which may be attributable to the method used for measuring ER, the species analyzed (rat, mouse, human) and/or the differentiation state of isolated primary cells. Very often tissues express both ER-xcex1 and ER-xcex2, but the receptors are localized in different cell types. In addition, some tissues (such as kidney) contain exclusively ER-xcex1, while other tissues (such as uterus, pituitary and epidymis) show a great predominance of ER-xcex1 (Couse et al., Endocrinology 138, 4613-4621, 1997; Kuiper et al., Endocrinology 138, 863-870, 1997). In contrast, tissues expressing high levels of ER-xcex2 include prostate, testis, ovaries and certain areas of the brain (Brandenberger et al., J. Clin. Endocrinol. Metab. 83, 1025-8, 1998; Enmark et al., J. Clinic. Endocrinol. Metabol. 82, 4258-4265, 1997; Laflamme et al., J. Neurobiol. 36, 357-78, 1998; Sar and Welsch, Endocrinology 140, 963-71, 1999; Shughrue et al., Endocrinology 138, 5649-52, 1997a; Shughrue et al., J. Comp. Neurol. 388, 507-25, 1997b).
The development of ER-xcex1 (Korach, Science 266, 1524-1527, 1994) and ER-xcex2 (Krege et al., Proc. Natl. Acad. Sci. USA 95, 15677-82, 1998) knockout mice further demonstrate that ER-xcex2 has different functions in different tissues. For example, ER-xcex1 knockout mice (male and female) are infertile, females do not display sexual receptivity and males do not have typical male-aggressive behavior (Cooke et al., Biol. Reprod. 59, 470-5, 1998; Das et al., Proc. Natl. Acad. Sci. USA 94, 12786-12791, 1997; Korach, 1994; Ogawa et al., Proc. Natl. Acad. Sci. USA 94, 1476-81, 1997; Rissman et al., Endocrinology 138, 507-10, 1997a; Rissman et al., Horm. Behav. 31, 232-243, 1997b). Further, the brains of these animals still respond to estrogen in a pattern that is similar to that of wild-type animals (Shughrue et al., Proc. Natl. Acad. Sci. USA 94, 11008-12, 1997c), and estrogen still inhibits vascular injury caused by mechanical damage (Iafrati et al., Nature Med. 3, 545-8, 1997). In contrast, mice lacking the ER-xcex2 develop normally, are fertile and exhibit normal sexual behavior, but have fewer and smaller litters than wild-type mice (Krege et al., 1998), have normal breast development and lactate normally. The reduction in fertility is believed to be the result of reduced ovarian efficiency, and ER-xcex2 is the predominant form of ER in the ovary, being localized in the granulosa cells of maturing follicles.
In summary, compounds which serve as estrogen antagonists or agonists have long been recognized for their significant pharmaceutical utility in the treatment of a wide variety of estrogen-related conditions, including conditions related to the brain, bone, cardiovascular system, skin, hair follicles, immune system, bladder and prostate (Barkhem et al., Mol. Pharmacol. 54, 105-12, 1998; Farhat et al., FASEB J. 10, 615-624, 1996; Gustafsson, Chem. Biol. 2, 508-11, 1998; Sun et al., 1999; Tremblay et al., Endocrinology 139, 111-118, 1998; Turner et al., Endocrinology 139, 3712-20, 1998). In addition, a variety of breast and non-breast cancer cells have been described to express ER, and serve as the target tissue for specific estrogen antagonists (Brandenberger et al., 1998; Clinton and Hua, Crit. Rev. Oncol. Hematol. 25, 1-9, 1997; Hata et al., Oncology 55 Suppl 1, 35-44, 1998; Rohlff et al., Prostate 37, 51-9, 1998; Simpson et al., J Steroid Biochem Mol Biol 64, 137-45,1998; Yamashita et al., Oncology 55 Suppl 1,17-22, 1998).
In recent years a number of both steroidal and nonsteroidal compounds which interact with ER have been developed. For example, Tamoxifen was originally developed as an anti-estrogen and used for the treatment of breast cancer, but more recently has been found to act as a partial estrogen agonist in the uterus, bone and cardiovascular system. Raloxifene is another compound that has been proposed as a SERM, and has been approved for treatment of osteoporosis. 
Analogs of Raloxifene have also been reported (Grese et al., J. Med. Chem. 40:146-167, 1997).
As for coumarin-based compounds, a number of structures have been proposed, including the following: Roa et al., Synthesis 887-888, 1981; Buu-Hoi et al., J. Org. Chem. 19:1548-1552, 1954; Gupta et al., Indian J. Exp. Biol. 23:638-640, 1985; Published PCT Application No. WO 96/31206; Verma et al., Indian J. Chem. 32B:239-243, 1993; Lednicer et al., J. Med. Chem. 8:725-726, 1965; Micheli et al., Steroids 5:321-335, 1962; Brandt et al., Int. J. Quantum Chemistry: Quantum Biol. Symposia 13:155-165, 1986; Wani et al., J. Med. Chem. 18:982-985, 1975; Pollard et al., Steroids 11:897-907, 1968.
Accordingly, there is a need in the art for compounds useful for treating a bone-resorbing disease, cancer, arthritis or an estrogen-related condition.
Citation or identification of any reference in Section 2 of this application is not to be construed as an admission that the reference is prior art to the present application.
The invention relates to compounds having the following general structure (1): 
and pharmaceutically acceptable salts thereof, wherein:
n is 2, 3 or 4;
R1 is hydrogen, C(xe2x95x90O)R2, C(xe2x95x90O)OR2, C(xe2x95x90O)NHR2, C(xe2x95x90O)NR2R3, or S(xe2x95x90O2)NR2R3;
R2and R3 are independently C1-8alkyl, C6-12aryl, C7-12arylalkyl, or a five- or six-membered heterocycle containing up to two heteroatoms selected from O, NR4 and S(O)q, wherein each of the above groups are optionally substituted with one to three substituents independently selected from R5 and q is 0, 1 or 2;
R4 is hydrogen or C1-4alkyl;
R5 is hydrogen, halogen, hydroxy, C1-6alkyl, C1-4alkoxy, C1-4acyloxy, C1-4thio, C1-4alkylsulfinyl, C1-4alkylsulfonyl, (hydroxy)C1-4alkyl, C6-12aryl, C7-12aralkyl, COOH, CN, CONHOR6, SO2NHR6, NH2, C1-4alkylamino, C1-4dialkylamino, NHSO2R6, NO2, or a five- or six-membered heterocycle, where each occurrence of R6 is independently C1-6alkyl;
X is hydrogen, halogen or trifluoromethyl; and
Y is halogen or trifluoromethyl.
The invention also relates to a method of obtaining a compound of formula (I), wherein R1 is H, by demethylation of a compound of formula (II).
The invention further relates to a method for inhibiting a cytokine in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for treating or preventing a bone-resorbing disease in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for treating or preventing cancer in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for treating or preventing arthritis in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for modulating gene expression in a cell expressing ER, comprising contacting the cell with an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for modulating gene expression in a tissue expressing ER, comprising contacting the cell with an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The invention further relates to a method for treating or preventing an estrogen related condition in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), or a pharmaceutically acceptable salt of the compound.
The present invention may be understood more fully by reference to the detailed description and examples, which are intended to exemplify non-limiting embodiments of the invention.
The invention relates to compounds of formula (I): 
and pharmaceutically acceptable salts thereof, wherein:
n is 2, 3 or 4;
R1 is hydrogen, C(xe2x95x90O)R2, C(xe2x95x90O)OR2, C(xe2x95x90O)NHR2, C(xe2x95x90O)NR2R3, or S(xe2x95x90O2)NR2R3;
R2 and R3 are independently C1-8alkyl, C6-12aryl, C7-12arylalkyl, or a five- or six-membered heterocycle containing up to two heteroatoms selected from O, NR4 and S(O)q, wherein each of the above groups are optionally substituted with one to three substituents independently selected from R5 and q is 0, 1 or 2;
R4 is hydrogen or C1-4alkyl;
R5 is hydrogen, halogen, hydroxy, C1-6alkyl, C1-4alkoxy, C1-4acyloxy, C1-4thio, C1-4alkylsulfinyl, C1-4alkylsulfonyl, (hydroxy)C1-4alkyl, C6-12aryl, C7-12aralkyl, COOH, CN, C(xe2x95x90O)NHOR6, S(xe2x95x90O2)NHR6, NH2, C1-4alkylamino, C1-4dialkylamino, NHSO2R6, NO2, or a five- or six-membered heterocycle, where each occurrence of R6 is independently C1-6alkyl;
X is hydrogen, halogen or trifluoromethyl; and
Y is halogen or trifluoromethyl.
In a preferred embodiment, the compounds of formula (I) are those wherein n=2 and R1 is hydrogen.
The invention further relates to a method for obtaining compounds of formula (I), wherein R1 is H, comprising the step of demethylating a compound of formula (II) shown below: 
or a pharmaceutically acceptable salt thereof, wherein n is 2, 3 or 4 and X and Y are as defined above.
The demethylation of compounds of formula (II) can be achieved using any method known in the art useful in the deprotection of phenolic methyl ethers. Examples of such methods can be found in Greene, T. W., Protective Groups in Organic Synthesis, Chapter 3, John Wiley and Sons, New York, 1981, pp. 88-92, which is incorporated herein by reference in its entirety. Preferably, demethylation proceeds by a method comprising contacting a compound of formula (II) with about 1.0 to about 50.0 molar equivalents of a demethylating agent such as iodotrimethylsilane, pyridine hydrochloride, hydrobromic acid, hydrochloric acid, hydroiodic acid, a Grignard reagent, a Lewis acid or a strong nucleophile. More preferably, the demethylating agent is aqueous HBR, more preferably as a mixture in acetic acid. In a more preferred embodiment, demethylation is achieved by heating the compound of formula (II), or a pharmaceutically acceptable salt thereof, in the presence of the demethylating agent, optionally in the presence of a solvent, preferably a carboxylic acid, at a temperature of about room temperature to about 200xc2x0 C., preferably at a temperature of about 100xc2x0 C. to about 160xc2x0 C. for 15 minutes to about 24 hours. In one embodiment, the demethylation reaction vessel is sealed, for example a sealed tube, to prevent solvent evaporation, particularly where the boiling point of the solvent is lower than the temperature of the demethylation reaction. The acid salt of compounds of formula (I), wherein R1 is H, can be obtained by isolating the compound directly from the demethylation reaction which can then be used to prepare the corresponding pharmaceutically acceptable salt. The free base form is available upon washing the acid salt with an appropriate base such as sodium hydroxide and isolating the compound.
The resulting compounds of formula (I), wherein R1 is H, that are produced by demethylation of compounds of formula (II), are useful as cytokine inhibitors as well as for the treatment or prevention of a bone-resorbing disease, cancer, arthritis or an estrogen-related condition. The compounds of formula (I), wherein R1 is H, that are produced by demethylation of compounds of formula (II) are also useful as intermediates in the synthesis of compounds of formula (I) wherein R1 is C(xe2x95x90O)R2, C(xe2x95x90O)OR2, C(xe2x95x90O)NHR2, C(xe2x95x90O)NR2R3, or S(xe2x95x90O2)NR2R3.
The compounds of formula (I) and pharmaceutically acceptable salts thereof (collectively, the xe2x80x9cbenzopyranone compoundsxe2x80x9d), are useful for treating or preventing a bone-resorbing disease, cancer, arthritis or an estrogen-related condition. The benzopyranone compounds are also useful for inhibiting a cytokine in a patient and modulating gene expression in a cell and/or tissue expressing ER. Thus, the compounds of this invention may be administered as a therapeutic and/or prophylactic agent.
As used herein, a xe2x80x9cC6-12arylxe2x80x9d is an aromatic moiety containing from 6 to 12 carbon atoms. In one embodiment, the C6-12aryl is selected from (but not limited to) phenyl, tetralinyl, and napthalenyl.
A xe2x80x9cC7-12aralkylxe2x80x9d is an arene containing from 7 to 12 carbon atoms, and has both aliphatic and aromatic units. In one embodiment, the C7-12aralkyl is an aryl group bonded directly through an alkyl group, such as (but not limited to) benzyl, ethylbenzyl (i.e., xe2x80x94(CH2)2phenyl), propylbenzyl and isobutylbenzyl.
A xe2x80x9cC3-12heterocyclexe2x80x9d is a compound that contains a ring made up of more than one kind of atom, and which contains 3 to 12 carbon atoms, including (but not limited to) pyrrolidinyl, pyrrolyl, indolyl, pyrazolyl, oxetanyl, pyrazolinyl, imidazolyl, imidazolinyl, imidazolidinyl, oxazolyl, oxazolidinyl, isoxazolinyl, isoxazolyl, thiazolyl, thiadiazolyl, thiazolidinyl, isothiazolyl, isothiazolidinyl, furyl, tetrahydrofuryl, thienyl, oxadiazolyl, piperidinyl, piperazinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolidinyl, 2-oxazepinyl, azepinyl, 4-piperidonyl, pyridyl, N-oxo-pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, tetrahydropyranyl, tetrahydrothiopyranyl, tetrahydrothiopyranyl sulfone, morpholinyl, thiomorpholinyl, thiomorpholinyl sulfoxide, thiomorpholinyl sulfone, 1,3-dioxolane and tetrahydro-1,1-dioxothienyl, dioxanyl, isothiazolidinyl, thietanyl, thiiranyl, triazinyl, and triazolyl.
A xe2x80x9cC4-16heterocyclealkylxe2x80x9d is a compound that contains a C3-12heterocycle as listed above linked to a C1-8alkyl.
A xe2x80x9cC1-8alkylxe2x80x9d is a straight chain or branched carbon chain containing from 1 to 8 carbon atoms, including (but not limited to) methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, and the like. Similarly, a xe2x80x9cC1-xalkyl has the same meaning, but wherein xe2x80x9cxxe2x80x9d represents the number of carbon atoms less than eight, such as C1-6alkyl.
A xe2x80x9csubstitutedxe2x80x9d C1-xalkyl, C6-12aryl, C7-12aralkyl, C3-12heterocycle, or C4-16heterocyclealkyl moiety is a C1-xalkyl, C6-12aryl, C7-12aralkyl, C3-12heterocycle, or C4-16heterocyclealkyl moiety having at least one hydrogen atom replaced with a substituent.
A xe2x80x9csubstituentxe2x80x9d is a moiety selected from halogen, xe2x80x94OH, xe2x80x94Rxe2x80x2, xe2x80x94ORxe2x80x2, xe2x80x94COOH, xe2x80x94COORxe2x80x2, xe2x80x94CORxe2x80x2, xe2x80x94CONH2, xe2x80x94NH2, xe2x80x94NHRxe2x80x2, xe2x80x94NRxe2x80x2Rxe2x80x2, xe2x80x94SH, xe2x80x94SRxe2x80x2, xe2x80x94SOORxe2x80x2, xe2x80x94SOOH and xe2x80x94SORxe2x80x2, where each occurrence of Rxe2x80x2 is independently selected from an unsubstituted or substituted C1-8alkyl, C6-12aryl, C7-12aralkyl, C3-12heterocycle or C4-16heterocyclealkyl.
A xe2x80x9chalogenxe2x80x9d is fluorine, chlorine, bromine or iodine.
The benzopyranone compounds can have chiral centers and can occur as racemates, racemic mixtures and as individual enantiomers or diastereomers. All such isomeric forms are included within the present invention, including mixtures thereof. Furthermore, some of the crystalline forms of the benzopyranone compounds can exist as polymorphs, which are included in the present invention. In addition, some of the benzopyranone compounds can also form solvates with water or other organic solvents. Such solvates are similarly included within the scope of this invention.
An estrogen xe2x80x9cagonistxe2x80x9d is a compound that binds to ER and mimics the action of estrogen in one or more tissues, while an xe2x80x9cantagonistxe2x80x9d binds to ER and blocks the action of estrogen in one or more tissues. Further, the term xe2x80x9cestrogen-related conditionxe2x80x9d encompasses any condition associated with elevated or depressed levels of estrogen, a selective estrogen receptor modulator (SERM) or ER. In this context, ER includes both ER-xcex1 and/or ER-xcex2, as well as any isoforms, mutations and proteins with significant homology to ER.
A xe2x80x9cpatientxe2x80x9d is an animal, including, but not limited to, an animal such a cow, monkey, horse, sheep, pig, chicken, turkey, quail, cat, dog, mouse, rat, rabbit, and guinea pig, and is more preferably a mammal, and most, preferably a human.
Although not intending to be limited by the following theory, particularly in the context of bone-resorbing diseases, it is believed that the benzopyranone compounds function by blocking cytokine production and/or by inhibiting formation of osteoclasts.
The present invention also relates to pharmaceutical compositions comprising an effective amount of a benzopyranone compound and optionally a pharmaceutically acceptable carrier or vehicle, wherein a pharmaceutically acceptable carrier or vehicle can comprise an excipient, diluent, or a mixture thereof. Other embodiments of the present invention include methods for treating or preventing bone-resorbing diseases, including, but not limited to, osteoporosis, metastatic bone cancer and hypercalcemia, osteolytic lesions with orthopedic implants, Paget""s disease, and bone loss associated with hyperparathyroidism; conditions associated with IL-6, including various cancers and arthritis; cancer, including breast cancer, prostrate cancer, colon cancer, endometrial cancer, multiple myeloma, renal cell carcinoma and cervical carcinoma; and arthritis, including adjuvant-, collagen-, bacterial- and antigen-induced arthritis, particularly rheumatoid arthritis. These methods comprise administering an effective amount of a benzopyranone compound to a patient in need thereof.
In addition, the benzopyranone compounds are useful for treating or preventing a wide range of estrogen-related conditions, including, but not limited to, breast cancer, osteoporosis, endometriosis, cardiovascular disease, hypercholesterolemia, prostatic hypertrophy, prostatic carcinomas, obesity, hot flashes, skin effects, mood swings, memory loss, prostate cancer, menopausal syndromes, hair loss (alopecia), type-II diabetes, Alzheimer""s disease, urinary incontinence, GI tract conditions, spermatogenesis, vascular protection after injury, endometriosis, learning and memory, CNS effects, plasma lipid levels, acne, cataracts, hirsutism, other solid cancers (such as colon, lung, ovarian, melanoma, CNS, and renal), multiple myeloma, lymphoma, and adverse reproductive effects associated with exposure to environmental chemicals or natural hormonal imbalances.
The benzopyranone compounds are also useful for oral contraception; relief for the symptoms of menopause; prevention of threatened or habitual abortion; relief of dysmenorrhea; relief of dysfunctional uterine bleeding; relief of endometriosis; an aid in ovarian development; treatment of acne; diminution of excessive growth of body hair in women (hirsutism); the prevention or treatment of cardiovascular disease; prevention and treatment of atherosclerosis; prevention and treatment of osteoporosis; treatment of benign prostatic hyperplasia and prostatic carcinoma obesity; and suppression of post-partum lactation. The benzopyranone compounds also have a beneficial effect on plasma lipid levels and as such are useful in treating and preventing hypercholesterolemia. The benzopyranone compounds are further useful in the treatment and prevention of breast and ovarian cancer.
In another embodiment, the invention relates to a method for inhibiting a cytokine in a patient, comprising administering to a patient in need thereof an effective amount of a compound of formula (I), (II) or a pharmaceutically acceptable salt of the compound.
In a further embodiment, the invention relates to a method for modulating gene expression in a cell expressing ER, comprising contacting the cell with an effective amount of a compound of formula (I), (II) or a pharmaceutically acceptable salt of the compound.
In a further embodiment, the invention relates to a method for modulating gene expression in a tissue expressing ER, comprising contacting the cell with an effective amount of a compound of formula (I), (II) or a pharmaceutically acceptable salt of the compound.
The benzopyranone compounds can be prepared according to the general reaction schemes (Route 1 and Route 2) shown below. 
Step 1: Fries Reaction
Reaction yields are 40% to 55% and the reaction has been run on gram to multiple kilogram scale. On smaller scale reactions POCl3 (solvent) and ZnCl2 have been used in place of the BF3 diethyl etherate.
Step 2: Coumarin Formation Reaction Summary
Reaction yields are typically 10% to 90% and the reactions have been run on a multiple gram scale. Powdered K2CO3 is essential for efficient reaction. Reactions have also been run by adding all reagents simultaneously instead of preactivating the acid as described above. Under these conditions slightly lower yields are obtained.
Step 3: Side-chain Introduction Reaction Summary
Reaction yields are typically 30% to 70% and the reactions have been run on multiple gram scale. Powdered K2CO3 is essential and granular material results in incomplete or prolonged reaction times. The reaction yield in the examples provided are our most recent efforts and the yields were lower than expected. In the case of the dichloro analog, product precipitated on the column during flash chromatography In general this is the highest yielding step of the reaction sequence. The side-chain has also been introduced as described in the alternative synthesis scheme.
Step 4: Demethylation Reaction Summary
Reaction yields are typically 60% to 75%. Sealed tube reaction minimizes HBr escape and greatly facilitates the reaction rate. Reactions run at atmospheric pressure require one day or more for completion. 
Methods of this invention involve administering an effective amount of a benzopyranone compound, or a pharmaceutical composition containing one or more of the same, to a patient in need thereof in an amount sufficient to treat the disease or condition of interest. To that end, the term xe2x80x9ctreatxe2x80x9d (or the related terms xe2x80x9ctreatingxe2x80x9d and xe2x80x9ctreatmentxe2x80x9d) means administration of a compound, typically in combination with an appropriate delivery vehicle or agent, to a patient that does not show signs of a disease or condition (e.g., prophylactic or preventative administration) or that does show signs of a disease or condition (e.g., curative or treatment administration). Further, the phrase xe2x80x9ceffective amountxe2x80x9d means a benzopyranone compound dose that, after a given time, results in the desired effect. For example, in the context of bone-resorbing disease, an effective amount results in bones mass that is statistically different from that of animals treated with placebo. Similarly, for cancer and arthritis, an effective amount is an amount sufficient to produce the desired effect on the cancerous or arthritic tissue.
The benzopyranone compounds can exist as a pharmaceutically acceptable salt of a compound of structure (I) or (II). The pharmaceutically acceptable acid addition salts of the benzopyranone compounds can be formed of the compound itself, or of any of its esters, and include the pharmaceutically acceptable salts which are often used in pharmaceutical chemistry. For example, salts may be formed with organic or inorganic acids. Suitable organic acids include maleic, fumaric, benzoic, ascorbic, succinic, methanesulfonic, benzenesulfonic, toluenesulfonic, acetic, oxalic, trifluoroacetic, propionic, tartaric, salicylic, citric, gluconic, lactic, mandelic, cinnamic, aspartic, stearic, palmitic, formic, glycolic, glutamic, and benzenesulfonic acids. Suitable inorganic acids include hydrochloric, hydrobromic, sulfuric, phosphoric, and nitric acids. Additional salts include chloride, bromide, iodide, bisulfate, acid phosphate, isonicotinate, lactate, acid citrate, oleate, tannate, pantothenate, bitartrate, gentisinate, gluconate, glucaronate, saccharate, ethanesulfonate, p-toluenesulfonate, and pamoate (i.e., 1,1xe2x80x2-methylene-bis-(2-hydroxy-3-naphthoate)) salts. The term xe2x80x9cpharmaceutically acceptable saltxe2x80x9d is intended to encompass any and all acceptable salt forms.
Pharmaceutically acceptable salts can be formed by conventional and known techniques, such as by reacting a compound of this invention with a suitable acid as disclosed above. Such salts are typically formed in high yields at moderate temperatures, and often are prepared by merely isolating the compound from a suitable acidic wash in the final step of the synthesis. The salt-forming acid may dissolved in an appropriate organic solvent, or aqueous organic solvent, such as an alkanol, ketone or ester. On the other hand, if the benzopyranone compound is desired in the free base form, it may be isolated from a basic final wash step, according to known techniques. For example, a typical technique for preparing hydrochloride salt is to dissolve the free base in a suitable solvent, and dry the solution thoroughly, as over molecular sieves, before bubbling hydrogen chloride gas through it.
The benzopyranone compounds can be administered to a patient orally or parenterally in the conventional form of preparations, such as capsules, microcapsules, tablets, granules, powder, troches, pills, suppositories, injections, suspensions and syrups. Suitable formulations can be prepared by methods commonly employed using conventional, organic or inorganic additives, such as an excipient (e.g., sucrose, starch, mannitol, sorbitol, lactose, glucose, cellulose, talc, calcium phosphate or calcium carbonate), a binder (e.g., cellulose, methylcellulose, hydroxymethylcellulose, polypropylpyrrolidone, polyvinylpyrrolidone, gelatin, gum arabic, polyethyleneglycol, sucrose or starch), a disintegrator (e.g., starch, carboxymethylcellulose, hydroxypropylstarch, low substituted hydroxypropylcellulose, sodium bicarbonate, calcium phosphate or calcium citrate), a lubricant (e.g., magnesium stearate, light anhydrous silicic acid, talc or sodium lauryl sulfate), a flavoring agent (e.g., citric acid, menthol, glycine or orange powder), a preservative (e.g, sodium benzoate, sodium bisulfite, methylparaben or propylparaben), a stabilizer (e.g., citric acid, sodium citrate or acetic acid), a suspending agent (e.g., methylcellulose, polyvinyl pyrroliclone or aluminum stearate), a dispersing agent (e.g., hydroxypropylmethylcellulose), a diluent (e.g, water), and base wax (e.g., cocoa butter, white petrolatum or polyethylene glycol). The effective amount of the benzopyranone compound in the pharmaceutical composition may be at a level that will exercise the desired effect; for example, about 0.1 mg to 100 mg in unit dosage for both oral and parenteral administration.
The benzopyranone compound can be usually administered one to four times a day with a unit dosage of 0.1 mg to 100 mg in human patients, but the above dosage may be properly varied depending on the age, body weight and medical condition of the patient and the type of administration. A preferred dose is 0.25 mg to 25 mg in human patients. One dose per day is preferred.
The dose of a benzopyranone compound to be administered to a human is rather widely variable and subject to the judgment of the attending physician. It should be noted that it may be necessary to adjust the dose of a benzopyranone compound when it is administered in the form of a salt, such as a laureate, the salt forming moiety of which has an appreciable molecular weight. The general range of effective administration rates of the benzopyranone compounds is from about 0.05 mg/day to about 100 mg/day. A preferred rate range is from about 0.25 mg/day to 25 mg/day. Of course, it is often practical to administer the daily dose of a benzopyranone compound in portions, at various hours of the day. However, in any given case, the amount of benzopyranone compound administered will depend on such factors as the solubility of the active component, the formulation used and the route of administration.
It is usually preferred to administer a benzopyranone compound orally for reasons of convenience. However, the benzopyranone compounds may equally effectively be administered percutaneously, or as suppositories for absorption by the rectum, if desired in a given instance.
The benzopyranone compounds can be administered as pharmaceutical compositions. The compositions can be in the form of tablets, chewable tablets, capsules, solutions, parenteral solutions, troches, suppositories and suspensions. Compositions can be formulated to contain a daily dose, or a convenient fraction of a daily dose, in a dosage unit, which may be a single tablet or capsule or convenient volume of a liquid.
The compositions can be readily formulated as tablets, capsules and the like; it is preferable to prepare solutions from water-soluble salts, such as the hydrochloride salt. In general, all of the compositions are prepared according to known methods in pharmaceutical chemistry. Capsules are prepared by mixing the benzopyranone compound with a suitable diluent and filling the proper amount of the mixture in capsules. The usual diluents include inert powdered substances such as starch of many different kinds, powdered cellulose, especially crystalline and microcrystalline cellulose sugars such as fructose, mannitol and sucrose, grain flours and similar edible powders.
Tablets are prepared by direct compression, by wet granulation, or by dry granulation. Their formulations usually incorporate diluents, binders, lubricants and disintegrators as well as the compound. Typical diluents include, for example, various types of starch, lactose, mannitol, kaolin, calcium phosphate or sulfate, inorganic salts such as sodium chloride and powdered sugar. Powdered cellulose derivatives are also useful. Typical tablet binders are substances such as starch, gelatin and sugars such as lactose, fructose, glucose and the like. Natural and synthetic gums are also convenient, including acacia, alginates, methylcellulose, polyvinylpyrrolidine and the like. Polyethylene glycol, ethylcellulose and waxes can also serve as binders.
A lubricant might be necessary in a tablet formulation to prevent the tablet and punches from sticking in the die. The lubricant can be chosen from such slippery solids as talc, magnesium and calcium stearate, stearic acid and hydrogenated vegetable oils. Tablet disintegrators are substances that swell when wetted to break up the tablet and release the compound. They include starches, clays, celluloses, algins and gums. More particularly, corn and potato starches, methylcellulose, agar, bentonite, wood cellulose, powdered natural sponge, cation-exchange resins, alginic acid, guar gum, citrus pulp and carboxymethyl cellulose, for example, can be used as well as sodium lauryl sulfate. Tablets can be coated with sugar as a flavor and sealant, or with film-forming protecting agents to modify the dissolution properties of the tablet. The compositions can also be formulated as chewable tablets, for example, by using substances such as mannitol in the formulation.
When it is desired to administer a benzopyranone compound as a suppository, typical bases can be used. Cocoa butter is a traditional suppository base, which can be modified by addition of waxes to raise its melting point slightly. Water-miscible suppository bases comprising, particularly, polyethylene glycols of various molecular weights are in wide use.
The effect of the benzopyranone compounds can be delayed or prolonged by proper formulation. For example, a slowly soluble pellet of the benzopyranone compound can be prepared and incorporated in a tablet or capsule, or as a slow-release implantable device. The technique also includes making pellets of several different dissolution rates and filling capsules with a mixture of the pellets. Tablets or capsules can be coated with a film that resists dissolution for a predictable period of time. Even the parenteral preparations can be made long-acting, by dissolving or suspending the benzopyranone compound in oily or emulsified vehicles that allow it to disperse slowly in the serum.